package interview;

import java.text.BreakIterator;
import java.util.*;

public class lc15 {
    public static void main(String[] args) {
        System.out.println(threeSum(new int[]{-1,0,1,2,-1,-4}));

    }
    public static List<List<Integer>> threeSum(int[] nums) {
        Arrays.sort(nums);
        List<List<Integer>> ans = new ArrayList<>();
        for (int i = 0; i < nums.length; i++) {
            if(nums[i] > 0)
                break;
            if(i > 0 && nums[i] == nums[i - 1])
                continue;
            int left = i + 1, right = nums.length -1;
            while (left < right){
                int sum = nums[i] + nums[left] + nums[right];
                if(sum == 0){
                    List<Integer> list = new ArrayList<>();
                    list.add(nums[i]);
                    list.add(nums[left]);
                    list.add(nums[right]);
                    ans.add(list);
                    while(left < right && nums[left] == nums[left + 1])
                        left++;
                    while(left < right && nums[right] == nums[right - 1])
                        right--;
                    left++;
                    right--;
                }
                else if(sum < 0)
                    left++;
                else
                    right--;
            }
        }
        return ans;
    }
}
